Choosing the right shade of grey paint depends on many factors since grey is often affected by light (natural and artificial) and other colors around it.

Try several tones on your walls; see what other colors you can use in your room to give some depth like blues, purples, reds and yellow.

Remember grey can change the tone towards another color once on the wall like light blue or green and even lilac, if that’s the case and you don’t like how it turned out just keep trying other grey samples until you find the right one. Thank you I hope this helps.